1869.] FLEEMING JENKIN. IO/ 



With regard to the fifth edition of the ' Origin,' he wrote to 

 Mr. Wallace, January 22, 1869) : 



" I have been interrupted in my regular work in preparing 

 a new edition of the ' Origin,' which has cost me much labour, 

 and which I hope I have considerably improved in two or 

 three important points. I always thought individual differ- 

 -ences more important than single variations, but now I have 

 come to the conclusion that they are of paramount import- 

 ance, and in this I believe I agree with you. Fleeming 

 Jenkin's arguments have convinced me." 



This somewhat obscure sentence was explained, February 2, 

 in another letter to Mr. Wallace : 



" I must have expressed myself atrociously ; I meant to 

 say exactly the reverse of what you have understood. 

 F. Jenkin argued in the * North British Review ' against single 

 variations ever being perpetuated, and has convinced me, 

 though not in quite so broad a manner as here put. I always 

 thought individual differences more important ; but I was 

 blind and thought that single variations might be preserved 

 much oftener than I now see is possible or probable. I men- 

 tioned this in my former note merely because I believed that 

 you had come to a similar conclusion, and I like much to be 

 in accord with you. I believe I was mainly deceived by 

 single variations offering such simple illustrations, as when 

 man selects." 



The late Mr. Fleeming Jenkin's review, on the ' Origin of 

 Species/ was published in the ' North British Review ' for June 

 1867. It is not a little remarkable that the criticisms, which 

 my father, as I believe, felt to be the most valuable ever 

 made on his views should have come, not from a professed 

 naturalist but from a Professor of Engineering. 



It is impossible to give in a short compass an account of 

 Fleeming Jenkin's argument. My father's copy of the paper 

 (ripped out of the volume as usual, and tied with a bit of 

 string) is annotated in pencil in many places. I may quote 



